People drown in baths and hot tubs all the time, although that's more because they fall asleep.
And people die from diving into the shallow end, as well... of course, unless it's your first day at a pool, what kind of lifeguard doesn't know what end of the pool is too shallow to dive into?
Yeah, but you hire lifeguards to be calm and responsible in a moment of crisis... If a lifeguard panics and injures herself instead of helping the people in trouble, what's the point?